LED light assembly with transparent substrate having array of lenses for projecting light to illuminate an area

Abstract

A light assembly includes a thermally conductive support structure, a plurality of light emitting diodes (LEDs) attached to a circuit board and thermally coupled to a heat sink and a single transparent substrate with a corresponding plurality of optical elements over the LEDs. Each of the optical elements include a first portion configured to direct light in a second direction, a second portion configured to direct light in a second lateral direction, and a third portion configured to direct light in a third direction.

What is claimed is: 
     
       1. A light assembly comprising:
 a thermally conductive support structure with an attachment point for securing the support structure to a supporting element; 
 a heat sink; 
 a substantially planar circuit board attached to the support structure; 
 a plurality of LEDs attached to the circuit board to form an array, the LEDs being thermally coupled to the heat sink; and 
 a single transparent substrate overlying all LEDs attached to the circuit board and including a corresponding plurality of optical elements; 
 wherein each optical element includes a first portion configured to direct light from the corresponding LED away from the circuit board in a first direction, a second portion configured to direct light from the corresponding LED away from the circuit board in a second direction, and a third portion configured to direct light from the corresponding LED away from the circuit board in a third direction so that the light is directed asymmetrically so as to illuminate a substantially rectangular area that is off-center relative to the light assembly. 
 
     
     
       2. The light assembly of  claim 1 , wherein, for each optical element, the second portion intersects with the first portion in a region between the first portion and the second portion, and wherein, for each optical element, the first portion and the second portion are shaped so that at least one surface normal of the first portion intersects with at least one surface normal of the second portion. 
     
     
       3. The light assembly of  claim 1 , wherein the heat sink includes a plurality of fins and wherein a portion of the heat sink is in direct contact with the support structure. 
     
     
       4. The light assembly of  claim 1 , further comprising:
 a second substantially planar circuit board attached to the support structure, a main surface of the second circuit board being parallel to a main surface of the circuit board; 
 a second plurality of LEDs attached to the second circuit board; and 
 a second single transparent substrate overlying all LEDs attached to the second circuit board. 
 
     
     
       5. The light assembly of  claim 1 , wherein the attachment point is coupled to an adjustable mount for attaching the support structure to a stationary object, wherein the adjustable mount has an angle of tilt that ranges between 0 degrees and 45 degrees relative to a plane parallel to the first and second directions. 
     
     
       6. A light assembly comprising:
 a thermally conductive support structure with an attachment point for securing the support structure to a supporting element; 
 a heat sink; 
 a substantially planar circuit board attached to the support structure; 
 a plurality of LEDs attached to the circuit board to form an array, the LEDs being thermally coupled to the heat sink; and 
 a single transparent substrate overlying all LEDs attached to the circuit board and including a corresponding plurality of optical elements; 
 wherein each optical element includes a first portion configured to direct light from the corresponding LED away from the circuit board in a first direction, a second portion configured to direct light from the corresponding LED away from the circuit board in a second direction, and a third portion configured to direct light from the corresponding LED away from the circuit board in a third direction so as to illuminate a substantially rectangular area; and 
 wherein the light assembly is configured to direct light from the LEDs towards the area in a manner that does not create hot spots or result in dead spots on the area regardless of whether all of the LEDs of the plurality of LEDs or some of the LEDs of the plurality of LEDs are functional. 
 
     
     
       7. The light assembly of  claim 6 , wherein the light assembly is further configured to provide illumination redundancy such that the failure of one to five of the LEDs will cause an illumination level of light emitted from the light assembly to decrease while a uniformity of the light emitted from the light assembly remains substantially the same. 
     
     
       8. The light assembly of  claim 7 , wherein the light assembly is further configured to provide illumination redundancy such that the average illumination to an area when all LEDs are functional and emitting light is no more than three times the average illumination to the area when two or fewer of the LEDs are not emitting light. 
     
     
       9. A light assembly comprising:
 a thermally conductive support structure with an attachment point for securing the support structure to a supporting element; 
 a heat sink; 
 a substantially planar circuit board attached to the support structure; 
 a plurality of LEDs attached to the circuit board to form an array, the LEDs being thermally coupled to the heat sink; and 
 a single transparent substrate overlying all LEDs attached to the circuit board and including a plurality of optical elements, an outer surface of the transparent substrate being an outer surface of the light assembly; 
 wherein each optical element includes a first portion configured to direct light from the corresponding LED away from the circuit board in a first direction, a second portion configured to direct light from the corresponding LED away from the circuit board in a second direction, and a third portion configured to direct light from the corresponding LED away from the circuit board in a third direction; and 
 wherein the light assembly is configured so that the light is directed asymmetrically so as to illuminate a substantially rectangular area that is off-center relative to the light assembly. 
 
     
     
       10. The light assembly of  claim 9 , wherein the light assembly is configured to direct light from the LEDs towards an area in a manner that does not create hot spots or result in dead spots on the area regardless of whether all of the LEDs of the plurality of LEDs or some of the LEDs of the plurality of LEDs are functional. 
     
     
       11. The light assembly of  claim 9 , wherein the transparent substrate is configured to provide illumination redundancy such that the average illumination to an area when all LEDs are functional and emitting light is no more than three times the average illumination to the area when two or fewer of the LEDs are not emitting light. 
     
     
       12. The light assembly of  claim 9 , wherein the heat sink includes a plurality of fins on a first side of the heat sink. 
     
     
       13. The light assembly of  claim 9 , wherein the single transparent substrate is attached to the circuit board, wherein the substrate when attached to the circuit board is configured to prevent a substantial amount of water from directly contacting a first surface of the circuit board. 
     
     
       14. The light assembly of  claim 9 , wherein:
 the single transparent substrate includes a first plurality of holes; 
 the heat sink includes a second plurality of holes; and 
 the light assembly further comprises a plurality of screws, wherein the screws attach the single transparent substrate to the heat sink by being fastened through the first of plurality holes of the substrate to the second plurality of holes in the heat sink. 
 
     
     
       15. The light assembly of  claim 9 , further comprising a reflector disposed within the thermally conductive support structure positioned adjacent to the plurality of LEDs, wherein a portion of the reflector has surfaces that are not coplanar with first or second sides of the circuit board, wherein the reflector includes surfaces configured to direct light emitted by each of the LEDs towards a direction away from the first side of the circuit board. 
     
     
       16. A light assembly comprising:
 a thermally conductive support structure with an attachment point for securing the support structure to a supporting element; 
 a heat sink; 
 a substantially planar circuit board attached to the support structure; 
 a plurality of LEDs attached to the circuit board to form an array, the LEDs being thermally coupled to the heat sink; and 
 a single transparent substrate overlying all LEDs attached to the circuit board and including a corresponding plurality of optical elements; 
 wherein each optical element includes a first portion configured to direct light from the associated LED in a first primary direction away from the circuit board, a second portion configured to direct light from the associated LED in a second primary direction away from the circuit board, and a third portion configured to direct light in a third primary direction away from the circuit board; 
 wherein the light assembly is configured so that the light is directed asymmetrically in the third direction so as to illuminate a substantially rectangular area that is off-center relative to the light assembly; and 
 wherein the light assembly is configured to direct light from the LEDs towards an area in a manner that does not create hot spots or result in dead spots on the area regardless of whether all of the LEDs of the plurality of LEDs or some of the LEDs of the plurality of LEDs are functional. 
 
     
     
       17. The light assembly of  claim 16 , wherein the light assembly is further configured to provide illumination redundancy such that the average illumination to an area when all LEDs are functional and emitting light is no more than three times the average illumination to the area when two or fewer of the LEDs are not functional and not emitting light. 
     
     
       18. The light assembly of  claim 16 , wherein the heat sink includes a plurality of fins extending in a direction away from the circuit board. 
     
     
       19. The light assembly of  claim 16 , wherein a portion of the heat sink is in direct contact with the support structure. 
     
     
       20. The light assembly of  claim 16 , wherein the heat sink is directly exposed to the outside atmosphere and is not entirely enclosed by the support structure. 
     
     
       21. The light assembly of  claim 16 , wherein the support structure and the heat sink are portions of a single integral component. 
     
     
       22. The light assembly of  claim 16 , wherein each optical element overlies a single associated LED and wherein each and every one of the plurality of LEDs has an overlying optical element. 
     
     
       23. The light assembly of  claim 16 , further comprising:
 a second circuit board attached to the support structure; 
 a second plurality of LEDs attached to the second circuit board; and 
 a second single transparent substrate overlying all LEDs attached to the second circuit board.